AU2019202177A1 - Improvements in Seed Destroying Impact Mill Assemblies - Google Patents

Abstract

Abstract A seed destroying impact mill assembly (10) comprising a mill shaft (16), a driven pulley (36), and at least one cage mill (28), wherein the driven pulley (36) is fixedly attached to the mill shaft (16) such that rotational drive may be transferred therebetween and the or each cage mill (28) is driven by the mill shaft (16), the mill shaft (16) being arranged so as to extend substantially horizontally such that the driven pulley (36) is positioned in a substantially vertical plane, whereby the driven pulley (36) may be driven by a drive pulley (40) also positioned in a substantially vertical plane. ljLF Figure 2 Figure 2 Z

Description

FIELD OF THE INVENTION [0001] The present invention relates to improvements in seed destroying impact mill assemblies.

[0002] More particularly, the impact mill assemblies of the present invention are intended to be mounted substantially horizontally at the rear of a combine harvester and in an orientation substantially perpendicular to the longitudinal orientation of the combine harvester.

[0003] The present invention further relates to a combine harvester comprising a seed destroying impact mill assembly as described herein.

BACKGROUND TO THE INVENTION [0004] When harvesting grain, combine harvesters cut the whole plant off near the base of the stalk, which is taken into the machine for threshing. The threshing process inside the combine separates the good or target grain from the chaff (secondary seeds and fine materials) and the straw (the stalk of the plant).

[0005] The good grain is kept inside the combine, and the straw and chaff are discharged from the back of the combine through a set of rotating knives that cut the straw into a finer product and spread it back onto the field. As part of the harvesting process, weed plants and their seeds are also taken into the combine. These weed seeds are passed through the machine and discharged back onto the field. Weed seeds can then germinate in following growing seasons and continue to contaminate future crops.

[0006] Unwanted plants or weeds in grain crops compete with the desired plants for water and nutrients resulting in lower yields and contamination of the final product. Typically, farmers will control these weeds by spraying herbicides onto the field multiple times throughout the year. However, the predominant weeds (such as ryegrass) are developing significant resistance to all the

-22019202177 29 Mar 2019 available herbicides. Herbicide resistance is becoming a significant issue in Australia, and over time the impact of herbicide resistance is expected to become more significant internationally.

[0007] The process by which most of the plant material is collected by the combine harvester presents an opportunity to destroy the weed seeds prior to discharge from the machine, by which they would preferably be rendered inert and prevented from germination in subsequent seasons. Such an approach provides a method by which a farmer might control weeds in cereal crops, particularly those plants that have developed herbicide resistance.

[0008] One system requires that a bin be towed behind the combine and all the chaff material collected. The towing of the bin and collection of chaff is cumbersome and draws power. The chaff material is taken to an area of the field and burnt in piles, which is time consuming. It is understood that burning the chaff removes nutrients from the soil when compared with letting it decompose naturally.

[0009] Another prior art system uses a mechanical mill to physically impact the weed seeds and destroy them. Initially, a separate machine was towed behind the combine. Subsequently, mills have been incorporated into the back of the combine, rather than having a separate machine towed behind it. Both options have included two cage mills, which utilise a series of concentric rotating cages, or a combination of rotating cages and stationary bars or screens. The chaff/seed mix is fed into the centre of the spinning cages, and is flung out of the cages, through the rotating bars. A series of impacts as the chaff/seed is flung from the cages is sufficient to destroy the majority of weed seeds.

[0010] Attempts to control weed growth utilising cage mills have, to date, provided two cage mills mounted on a vertical shaft at the rear of the combine harvester, such that the cage mills rotate around the vertical shaft in a horizontal plane. The drive for such cage mills is provided by a drive pulley mounted toward the rear of all combine harvesters. This pulley is mounted so as to sit in a substantially vertical plane and is driven by a horizontally oriented shaft normally used to drive straw choppers. As the drive pulley is mounted in a different orientation to the cage mills, it cannot be used to directly drive the mills.

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-3Other drive systems are required to transfer power to the cage mills, such as a right-angle gearbox and a series of belts, or using hydraulic pumps and motors. Both of these arrangements are costly, require significant maintenance, and gearboxes and hydraulic pumps can generate heat. Anything that presents a fire risk, such as an overheating gear box, is a significant risk in an agricultural environment, particularly one amongst dry chaff and straw.

[0011] One object of the present invention is to provide a seed destroying impact mill assembly that overcomes substantially the abovementioned problems of the prior art, or at least provides a useful alternative thereto.

[0012] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to formed part of common general knowledge as at the priority date of the application.

[0013] Throughout the specification, unless the context requires otherwise, the word “comprise” or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integer.

[0014] The term “seed destroying” is to be understood to refer to a physical impact or effect imparted on an unwanted seed, including weed seeds, or other unwanted organic material, unless the context clearly requires otherwise.

[0015] The terms “vertical” and “horizontal”, or variations thereof used herein, are to be understood to be relative to a plane described by the or each axle of the wheels supporting the combine harvester on which the present invention may be provided. By extension, the terms will also be generally relative to a surface over which the combine harvester may be working.

SUMMARY OF THE INVENTION [0016] In accordance with the present invention there is provided a seed destroying impact mill assembly comprising a mill shaft, a driven pulley, and at least one impact mill, wherein the driven pulley is fixedly attached to the mill shaft such that rotational drive may be transferred therebetween and the or each

-42019202177 29 Mar 2019 impact mill assembly is driven by the mill shaft, the mill shaft being arranged so as to extend substantially horizontally such that the driven pulley is positioned in a substantially vertical plane, whereby the driven pulley may be driven by a drive pulley also positioned in a substantially vertical plane.

[0017] Preferably, the impact mill comprises a plurality of rotating impact components operating inside one or more screens, whereby the rotating impact components are driven by the rotation of the mill shaft, arranged within a shroud, the shroud having an outlet by which material may pass from the impact mill, the outlet being positioned at an upper level in the shroud, at a point above a horizontal plane described by, and that intercepts, the mill shaft.

[0018] Preferably, the impact mill assembly comprises two impact mills.

[0019] Still preferably, the impact mills are mounted on a single mill shaft in a spaced apart manner.

[0020] Still further preferably, a conveyor is provided between the two iimpact mills. The conveyor is preferably a bi-directional conveyor whereby material to be milled that is introduced to the conveyor is directed laterally to the impact mills.

[0021] Preferably, the impact mill assembly comprises a housing comprising in part the shroud of the or each impact mill, and further comprising a conveyor housing.

[0022] Still preferably, the housing still further comprises a chute that communicates with the conveyor housing, whereby material entering the impact mill assembly may be directed to the conveyor.

[0023] Preferably, one or more fans are provided to assist the feeding of unwanted seeds and chaff into the or each weed destroying impact mill.

[0024] The present invention further provides an impact mill assembly and combine harvester combination, wherein the impact mill assembly is as described hereinabove, the drive pulley being provided on the combine harvester.

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-5 [0025] The present invention still further provides a mounting arrangement for an impact mill assembly on a combine harvester, wherein the impact mill assembly is as described hereinabove, the drive pulley being provided on the combine harvester.

BRIEF DESCRIPTION OF THE DRAWINGS [0026] The present invention will now be described with reference to one embodiment thereof and the accompanying figures, in which:Figure 1 is a plan view of a combine harvester showing an impact mill assembly in accordance with the present invention provided at the rear of the machine, showing in particular the orientation of the mill shaft relative to the direction of travel of the combine;

Figure 2 is an upper isometric view of the impact mill assembly of Figure

1, showing the housing and shrouds in place;

Figure 3 is a side view of the impact mill assembly of Figure 1, showing the v-belt and drive pulley arrangement thereof;

Figure 4 is an isometric view of the impact mill assembly of Figure 1, showing a part of the housing removed to display the impact mills, and the bi-directional screw conveyor;

Figure 5 is a sectional view through the centre of the impact mill assembly of Figure 1, showing the typical impact mill, screen and conveyor assembly provided about the substantially horizontal mill shaft;

Figure 6 is a sectional view of the impact mill assembly of Figure 1, showing the cage mill within the shroud;

Figure 7 is an upper isometric view of the impact mill assembly of Figure

1, showing all shrouds and housing removed;

Figure 8 is an upper isometric view of the impact mill assembly of Figure

1, showing all shrouds and housing removed, and with the screens also removed to show the arrangement of the impact bars therein; and

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-6Figure 9 is a top plan view of the impact mill assembly of Figure 1, showing all shrouds and housing removed, and with the screens removed to show the arrangement of the impact bars therein.

DESCRIPTION OF PREFERRED EMBODIMENT [0027] Embodiments of the present invention will now be described with reference to the accompanying Figures. The inventive concepts of the present invention may be embodied in different forms and should not be construed as limited to the embodiments described in this specification. The terminology used in this specification is for the purpose of describing particular embodiments and is not intended to be limiting of the invention. The singular forms ‘a’, ‘an’ and ‘the’ are intended to include plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms ‘comprises’, ‘comprising’, ‘includes’, and/or ‘including’ specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

[0028] The present invention provides an improved seed destroying impact mill assembly, a drive and mounting arrangement for impact mills that are positioned at the rear of a combine such that the axis of rotation is substantially horizontal and perpendicular to the intended direction of travel of the combine. The present invention also provides a combine harvester (or ‘combine’) that incorporates an improved seed destroying impact mill assembly as described herein.

[0029] A combine discharges the waste products from the rear of the machine, typically consisting of straw, unsuitable seeds, weed seeds and chaff. This discharge is intercepted by the present invention in or on the combine harvester prior to discharge, such that the unsuitable seeds and weed seeds can be separated from the straw and diverted into the seed destroying cage mills.

[0030] The impact mills destroy the majority of unwanted seeds by mechanical action and thereby hinder future germination thereof that would contaminate fields and crops. The destroyed product is discharged from the improved impact mill assembly of the present invention back onto the field.

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-7 [0031] The impact mills are fixed to a horizontal shaft that is mounted on bearings along the rear of the combine harvester, perpendicular to the direction of machine travel and parallel to the axles of the combine. This mounting arrangement allows for a greatly simplified drive arrangement compared to other mill orientations. The shaft, and therefore the impact mills, can be driven by a single belt arrangement that connects to existing pulleys on the combine harvester, without having to turn that drive through 90°.

[0032] In Figure 1 there is shown a seed destroying impact mill assembly 10 provided on a rear 12 of a combine harvester 14. The impact mill assembly 10 comprises a single mill shaft 16 oriented substantially horizontally, generally parallel to axles 18 of the combine 14, and substantially perpendicular to a direction of travel 20 of the combine 14.

[0033] The impact mill assembly 10 of the present invention further comprises a housing 22, a pair of rolling element bearings 24, a screw conveyor 26, and a pair of mill assemblies 28, best seen in Figures 5 to 8.

[0034] The housing 22 comprises an internal product handling chute 30, whereby the chute 30 and barriers (not shown) inside the combine 14 allow preferential selection of unwanted seeds and chaff and the direction of this product into the chute 30 and housing 22, toward the impact mills 28. A straw product (also not shown) that does not contain seed material is separated and diverted in known manner, such that it bypasses the impact mills 28.

[0035] The housing 22 further comprises a conveyor housing portion 32 into which the chute 30 feeds, and which is located intermediate the two mill assemblies 28. The housing 22 still further comprises a pair of shrouds 34, each shroud 32 being provided about a respective mill assembly 28, as best seen in Figures 5 and 6.

[0036] The impact mills 28 are fixed to the mill shaft 16 mounted on the rolling element bearings 24. As noted above, the mill shaft 16 is positioned horizontally along the rear 12 of the combine harvester 14 such that it is perpendicular to the direction of travel 20 of the combine 14, and substantially parallel to the axles 18 thereof. The mill shaft 16 is driven and rotates accordingly whilst supported by the bearings 24.

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-8[0037] The mill shaft 16 has fixedly provided at or about one end thereof a driven pulley 36, positioned such that rotation of the pulley 34 directly causes rotation of the mill shaft 16. The driven pulley 36 is driven, by way of a v-belt 38, by a driven pulley 40. The drive pulley 40 is provided on the combine 14 and is arranged so as to be in a substantially vertical plane. The driven pulley 36 is similarly in a vertical plane. In this manner there is no requirement to turn or rotate the plane of rotation when imparting or transferring drive to the mill shaft

16.

[0038] A tension pulley 42 may be provided that is positioned so as to bear against, and maintain tension in, the v-belt 38, as seen in Figures 3, 7 and 8. The tension pulley 42 can be operated so as to transfer drive to the driven pulley 36. That is, if the v-belt 38 is not under tension then drive is not transferred.

[0039] The size ratio between the drive pulley 40 provided on the combine 14, and the driven pulley 36 on the mill shaft 16 is selected by a user (not shown) to provide the desired shaft speed.

[0040] This arrangement allows the impact mills 28 to be fixed to the mill shaft 16 such that their axis of rotation is substantially horizontal and generally perpendicular to the direction 20 of travel of the combine harvester 14. The orientation of the mill shaft in the present invention significantly simplifies the drive arrangement necessary to rotate the mill assemblies 28 when compared with arrangements of the prior art that position the mill assemblies with their axis of rotation in a vertical orientation.

[0041] The mill shaft 16 has provided thereon a conveyor 44, whereby unwanted seeds and chaff entering the conveyor housing 32 may be transferred to the impact mills 28. The conveyor 44 is located between the impact mills 28 and is provided in two separately fluted portions 46 and 48, such that fluted portion 46 is arranged and oriented to feed laterally into one impact mill 28, whilst the fluted portion 48 is arranged and oriented to feed laterally into the other impact mill 28, as best seen in Figure 5.

[0042] Each impact mill 28 comprises a plurality of concentric or co-axial stationary screens 50 located about the mill shaft 16. The screens 50 have provided therein a plurality of apertures 52. Between the screens 50 are

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-9 provided rotating impact components, for example impact bars or cages 54, the rotating cages 54 being defined by rods 56 that are arranged to extend laterally and in parallel to the mill shaft 16, as is best seen in Figures 5 to 9.

[0043] The shroud 34 provided about each cage mill assembly 28 further comprises an outlet 58, whereby destroyed unwanted seed and chaff is discharged therefrom. The outlet 58, as can be seen in Figures 2, 3 and 6, is located at an upper level in the shroud 34, at a point above a horizontal plane described by, and that intercepts, the mill shaft 16. This arrangement allows the unwanted seed and chaff to stay inside the impact mill 28 longer than is experienced with the vertical arrangements of the prior art, before the destroyed seed is discharged, and thereby improves the efficiency of seed destruction.

[0044] It is envisaged that only a single impact mill may be provided. Where multiple impact mills are used they may be mounted on a common shaft as described hereinabove, or on separate substantially horizontal shafts, and still realise many of the benefits of the present invention.

[0045] It is still further envisaged that one or more fans may be used to assist the feeding of unwanted seeds and chaff into the or each weed destroying impact mill.

[0046] As can be seen from the above description, the impact mill assembly of the present invention, and a combined impact mill assembly and combine of the present invention, and an impact mill assembly mounting arrangement of the present invention, each allow drive to be transferred to the or each impact mill in a manner such that no right angle gearbox is required. Speaking generally, the drive for the mill shaft is not required to be tilted or rotated. Rather, the drive is passed directly, in the same plane, from the drive pulley to the driven pulley, the driven pulley in turn passing that imparted rotational drive directly to the mill shaft, which is oriented so as to be substantially parallel with the axles of the combine, and substantially parallel with a shaft driving the drive pulley. Additionally, the arrangement of the outlet for destroyed unwanted seed and chaff is such that the unwanted seed and chaff is retained for a period within the

- 102019202177 29 Mar 2019 impact mills, thereby increasing the efficiency of unwanted seed destruction relative to prior art arrangements described herein.

[0047] Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention.

Claims (11)

1. 2019202177 29 Mar 2019

   The claims defining the invention as are follows:

   1. A seed destroying impact mill assembly comprising a mill shaft, a driven pulley, and at least one impact mill, wherein the driven pulley is fixedly attached to the mill shaft such that rotational drive may be transferred therebetween and the or each impact mill is driven by the mill shaft, the mill shaft being arranged so as to extend substantially horizontally such that the driven pulley is positioned in a substantially vertical plane, whereby the driven pulley may be driven by a drive pulley also positioned in a substantially vertical plane.
2. 2. The impact mill assembly of claim 1, wherein the or each impact mill comprises rotating impact components operating inside one or more screens, whereby the rotating impact components are driven by the rotation of the mill shaft, arranged within a shroud, the shroud having an outlet by which material may pass from the impact mill, the outlet being positioned at an upper level in the shroud, at a point above a horizontal plane described by, and that intercepts, the mill shaft
3. 3. The impact mill assembly of claim 1 or 2, wherein the impact mill assembly comprises two impact mills.
4. 4. The impact mill assembly of claim 3, wherein the impact mills are mounted on a single mill shaft in a spaced apart manner.
5. 5. The impact mill assembly of claim 3 or 4, wherein a conveyor is provided between the two impact mills.
6. 6. The impact mill assembly of claim 5, wherein the conveyor is a bidirectional conveyor whereby material to be milled that is introduced to the conveyor is directed laterally to the impact mills.
7. 7. The impact mill assembly of claim 5 or 6, wherein the impact mill assembly comprises a housing comprising in part the shroud of the or each impact mill, and further comprising a conveyor housing.

   - 122019202177 29 Mar 2019
8. 8. The impact mill assembly of claim 7, wherein the housing still further comprises a chute that communicates with the conveyor housing, whereby material entering the impact mill assembly may be directed to the conveyor.
9. 9. The impact mill assembly of any one of the preceding claims, wherein one or more fans are provided to assist the feeding of unwanted seeds and chaff into the or each weed destroying impact mills.
10. 10. An impact mill and combine harvester combination, comprising a combine harvester on which is provided the impact mill assembly of any one of claims 1 to 9.
11. 11. A mounting arrangement for an impact mill assembly on a combine harvester, comprising the impact mill assembly of any one of claims 1 to 9, wherein the drive pulley is provided on a combine harvester.